Lifting device



April 30,1935. J. F. H. LANGE LIFTING' DEVICE Filed July 19, 1934 Patented Apr. 30, 1935 UNITED STATES PATENT oFFrcE Germany,

assigner to Kampnagel Aktiengesellschaft (vormals Nagel & Kaemp), Hamburg, Germany Application July 19, 1934, Serial No. 736,090

Germany July 22, 1933 8 Claims. (Cl. 2511-172) My invention relates to improvements in lifting devices or cranes intended for lifting floating loads, such as hydro-aeroplane, from, or launching such loads in, a rough sea which-imparts to the load anirregular reciprocatory motion relative to the lifting device.

It is an object of my invention to provide means eliminating sudden jerks which are liable to be exerted by the agitated loa'd on the crane when the lifting rope is suddenly tautened and to injure the load and the lifting device.

Anotherobject is to provide means which will lift the floating load smoothly from the 'crests of the waves with a gradually accelerated speed; to provide means which will facilitate the job of securing the hook to the iioating load, for instance the hydro-aeroplane, and to provide a semi-automatic controlling equipment which facilitates the operation.

I attain these objects by the provision of two different driving systems which act conjointly on the hook of the winch, the main driving system including a lifting motor serving to lift or to lower the load from`or on the sea, whereas an auxiliary driving system including a comparatively small rope-tautening motor serves the sole purpose of lifting and lowering the hook during the up and down movement of the iioating load in synchronism with this movement. Preferably, bothdriving systems operate on a single winding drum independently and simultaneously.

The auxiliary driving system may be preferably provided with a ratchet or similar means preventing a retrograde turn and this ratchet isl adapted to be put in operation or to be disabled under electromagnetic control from a switch or other manually operable member installed in the operators cabin, interlocks being provided preventing the ratchet means from being disabled or enabled unless the auxiliary driving system operates in lifting direction.

If the main motor should operate in the lowering direction at the instant when the operator shifts the switch, this shifting will be effective only to prepare the release or engagement of the ratchet and the actual release or engagement will not take place until the auxiliary driving system is reversed to operate in the lifting direction.

'I'he power of the auxiliary driving system is just suicient to rapidly pull the lifting rope taut, after the ,hook has been secured to the hydroaeroplane, and to keep the rope taut under a slight tension, but is too small to interfere with the up and down movement of thehydro-aeroplane on the sea, if the ratchet is disabled. After the rope has been pulled taut, the small auxiliary motor remains energized and, when the hydro-aeroplane is lowered by the waves, it will overcome the torque exerted by the motor and will turn it in lowering direction. During this floating movement of the hydro-aeroplane on the sea the ratchet means remain completely disabled. When the operator wishes to lift the hydroaeroplane, he slowly starts the main lifting motor and prepares the engagement of the ratchet by operation of the switch above referred to.

As soon as the hydro-aeroplane willv be lifted by the waves, thereafter, the ratchet will be automatically engaged and will prevent any subsequent downward movement of the lifting hook. When the lifting motion caused by the waves approaches the point of reversal and has slowed down to a certain extent, it will be overtaken by the lifting motion imparted to the hook by the slowly operating main driving system and at the `instant in which both upward motions, Vthat caused by the waves and that caused by the main driving system, have the same speed, the load will be gradually lifted from the waves without any jerk. A similar operation takes place when the load is to be lowered on the agitated sea. The hydro-aeroplane attached to the hook is slowly lowered by the main driving system while the auxiliary motor is energized, but is unable owing to its limited power to pull in the rope subject to the heavy weight ofthe load. During this phase of the operation, the ratchet is still in engaged condition. When the hydro-aeroplane ap- -proaches the crests of the waves, the operator slows down the main motor to a small lowering speed and operates the switch so as to prepare the disengagement of the ratchet. However, the

ratchet will not be actually disengaged at this l time because the actual disengagement is conditional upon motion of the auxiliary motor .in the lifting direction. The auxiliary motor will operate in the lifting sense, however, and pull in the rope notwithstanding the simultaneous operation of the main motor, as soon as the hydro-aeroplane touches the waves and is lifted by the crests of the same. automatically released and this will permit the hydro-aeroplane to float freely on the sea, owing to the reduction of the lifting power to the small force exerted by the auxiliary motor after the release of the ratchet. l

A preferred embodiment of my invention 1n which the main driving system and the auxiliary driving system are cooperatively connected4 with a common winding drum, is illustrated on the accompanying drawing.

Fig. 1 shows a diagrammatic axial section through the winch, the two driving motors bemg shown in elevation.

Fig. 2 is an elevation of the electromagnetically controlled ratchet, partly in section along line` 2 2 of Fig. 1. A

Fig. 3 shows the circuit arrangement including an automatic switch responsive to the reversal At this very instant the ratchet will be of the auxiliary motor, the switch being illustrated in an enlarged elevational section taken along line 3-3 of Fig. 1. y

The winding drum II)A on which the rope II carrying the hook I2v is wound is adapted to be operated by the main motor I3 and/or the auxiliary motor I4 'through the intermediary of a differential gear. The casing of the main motor I3 which is mounted on the support cf the lifting device, for instance on the structure of the crane diagrammatically indicated at I5, forms a trunnion I6 which is coaxially arranged in relation to the windingr drum I0 and rotatably supports a gear case I1 which is bolted to the drum. There is also journalled on the trunnion I6 a boxshaped planet gear carrier I8 which is rigidly attached to a shaft I9. 'Ihe shaft I9 extends coaxially through the-drumv I0 and its free end is rotatably supported in a bracket 20 and carries an attached gear 2| meshing with a pinion 22 coupled to the auxiliary electric motor I4. The drum I0 has an end wall 23 and a partition 24 which are both rotatably journalled on shaft I9. The planet gear carrier I8 carries one1or more planetary gears 2 5 which meshwith'the` pinion 26 of the electric motor I3 and with an internally toothed rim 21 attached to the gear case I1.

28 indicates an -electromagnetically operated brake of well-known structure which arrests motor I3 whenever the current is cut off and the motor is at rest but is automatically lifted when the motor I3 is started.

Ona drum 5I! attached to shaft I9 there is fastened a ring 30 provided with ratchet teeth adapted to be engaged by ratchet pawls 3I whichl are yieldingly held in engagement by springs 32. Solenoids 33 are provided which may disengage the pawls upon energization. As shown in Fig. 2, the solenoids 33 are pivoted on brackets 34 and their cores are attached to rods 35 which are linked to the ratchet pawls and are surrounded by the springs 32.

Moreover, a split slip ring 36 is resiliently clamped on shaft 29 of the auxiliary motor by springs 31, as shown in Fig. 3. The split slip ring carries a piece 38 of insulating material in which a pair of contacts connected to wires 39 and 40 is ern-- and 48. It will be realized that either coil 41 or coil 48 will be energized depending upon the position of switch 45 provided, that shaft 29 turnsiin clockwise direction and, therefore, presses the contacts embedded in the insulating blocks upon each other through the intermediary of the slip ring 36. The coils 41, 48 act oppositely on a relay switch 49 included in the circuit 53 of the solenoids 33.

For a clear understanding of the operation let us rst consider the conditions prevailing when shaft 29 turns in clockwise direction with reference to Fig. 3 and when the manual switch 45 ass'umes the position shown in Fig. 3. In this event the contacts will be closed and the coil 41 will be energized pulling the relay switch 49 into the position shown in full lines, thereby dpe-energizing the solenoids 33. The springs32 will keep the ratchet pawls 3| in engaged condition. Shaft 29 turning will cause shaft I9 to turn anti-clockwise with reference to Fig. 2. If now switch 45 is shifted from the position shown in Fig. 3 to its left position, this will immediately energize coil 48 and thereby close switch 49. The consequent energization of solenoids 33 will disengage the ratchet pawls.

As long as the load of the hydro-aeroplane acts on the winding drum I0, it will exert a torque on shaft I9' and shaft 29 so as to separate the slip ring contacts, thereby preventing any control of the ratchet by the manual switch 45.

Owing to the differential action of the epicyclic gear, the main motor I3 cannot operate the winding drum to lift the load unless the ratchet is engaged because with a disengaged ratchet an operation of the main motor I3 will simply cause an idle turn of shaft I9 and of the auxiliary motor I4, while the winding drum I0 is arrested by the load. l

Therefore, the lifting operation of winding drum I0 by the main motor I3 is conditional upon the engagement of the ratchet 30, 3I or, in other words, upon a preceding energization of coil 41 or, still in other words, upon the position of switch 45 in theposition shown in Fig. 3. It will also appear from the foregoing consideration that the slip ring contacts'will remain separated and will prevent a release of the ratchet so long vas the winding drum I0 is subjected to the load. Not

until the lifting rope will be slackenedand will permit the auxiliary motor to operate in the lifting sense, will the slip ring contacts be closed and will release the ratchet if switch 45 has been shifted to the required position. Subsequent to this release the winding drum I0 cannot be subjected to the full load but will be subjected to the small torque only exerted by the auxiliary motor I4 which is just suicient to keep the lifting rope taut. While the control switch 45 of the ratchet may be shifted by the operator at any time, this will have no immediate. effect during the period in which the hook I2 carries the load, or is pulled downwardly by the load, but will only prepare the engagement or disengagement of the ratchet and the actual controlling operation will not take place until the auxiliary motor operates in the lifting sense upon relief of hook I2 from the load and closes the slip ring contacts. While I prefer the use of an electric auxiliary motor I4, any other suitable source of power may be employed, for instance a weight attached to a rope which is wound on a special drum coupled to inion 22. If desired, I may arrange motor I4 inside of drum I0, the armature being directly carried by shaft I9 and the pole pieces and pole windings by the drum I0.

The differential effect on the hook I2 may be attained by means other than a planetary gear, for instance by two separate drums, one being driven by the main n 'iter and the other by the auxiliary motor, these drums carrying the ends of a single rope which is reeved over a pulley attached to the hook.

In order to facilitate the difficult job of attaching or detaching the heavy hook I2 to or'from the floating hydro-aeroplane while the latter moves up and down, I prefer the provision of special means causing the hook I2 to be lifted and lowered in synchronism withthe hydro-aeroplane. before the actual attachment or after the detachattached to hook I2. This auxiliary rope 5I which tioned driving system and may be of light material, so that it can be easily handled, is first attached to the hydro-aeroplane turning shaft I9 in synchronism with the move-` mentsof the. hydro-aeroplane relative to the crane I5. The motion of shaft I9 is transmitted to the windingdrum I0, to the rope II and to the hook I2, and the latter will be moved up and down in the same manner asthe hydro-aeroplane so as to be kept spaced from the same at a certain distance which may be adjusted, as desired, by operation of motor I3. In other words, the distance of the hook I2 from the hydro-aeroplane will not be affected by the waves but can be solely controlled by motor I3. Thus, any collision between the heavy hook I2 and the hydroaeroplane will be avoided and the hook may be secured to thehydro-aeroplane at' leisure. After the hook has been attached to the hydro-aeroplane, the auxiliary rope 5I may be disconnected again. Y A

` Similarly, the rope 5I is fastened to the hydroaeroplane after the same has been launched in the sea, as described, preparatory to the detachment of the hook, thus preventing a collision ofthe plane with the detached hook.

A It is obvious that my invention is capable of `numerous modications without departing from the invention as set forth in the following claims.,

What I 'claim is: 1. Device for lifting and launching objects from and in the sea comprising the'combination with a common windingdrum and a lifting rope adapted izo-be attached to thevload. of two driving systems of different power, one system being adapted to pull and ykeep said rope taut and the lother system being adaptedto lift,A or lower said load, and of means for `preventing a load-lowering motion of said flrst-nientioned-'system. k2. Device for lifting and launching objects from and in the sea comprising alhoole adapted to be Iattached to the load, two driving systems of different' power ,differentially connectedgfwith said hook, a ratchetdevice coordinated to the less.

powerful driving system, means to ldisable or en. able said ratchet device, and a mechanism respon*v .sive to a reversal of movement of the last menpowerfulmotorE electromagnetic means to disable ratchet, a slip ring switchic'o-v ordinated to said less 'powerful motor and `-re,-- sponsiveto a( reversal of movement of the same or" enable said and adapted to control said electromagnetic 'means and a manual switch controlling said j. electromagnetic means conjointly with said slip ring switch'.`

-4gnevice for 1iftirgand launching cbjects from adapted to controlsaid and in the sea comprising the combination with a lifting rope adapted to be attached to the load of two driving motors of different power, one motor being dimensioned and designed to exert a continuous pull on said rope which is too small to lift said load but suiicient to keep said rope taut, and

h the other motor being adapted to lift or lower said in any suitable manner. This has thecffect of 1oad, and of means differentially connectingsaid motors with said rope so as to enable them to act thereon simultaneously but independently.

5. Mechanism for lifting oatmg loads, such as seaplanes, from a rough sea comprising a winch, a lifting rope, a inain driving mechanism adapted to operate said winch for lifting or loweringthe load, an auxiliary driving mechanism adapted to operate` said winch for pulling and keeping the lifting rope taut, means adapted to prevent a retrograde. operation of Asaid auxiliary driving mechanism, shiftable means adapted-to render said rst mentioned means effective or ineffective. and means adapted to prevent the operation of said shiftable means as long as the load operates, or tends to operate, said auxiliary driving mechanism in lowering direction. r 6. Mechanism for lifting iioating loads, such as seaplanes, from a rough sea comprising a winch,

a lifting rope, `a main driving mechanism adapted to operate said winch for lifting or lowering -the load, an auxiliary driving mechanism adapted to operate said winch for pulling and keeping the lifting rope Itaut', means adapted to prevent-a retrograde loperation of said auxiliary driving said first mentioned means effective or ineectlve. and means adapted to delay the operation of said shiftable meansuntil the auxiliary mechanism operates in lifting direction.

A'1. Mechanism for lifting oating loads, such as seaplaneairom a rough sea comprising a winch including a main winding drum; a lifting rope adapted to be wound thereon, aload-carrying hook carried bythe lifting rope, an auxiliary drivmechanism for said winch adapted to pull and keep the lifting rope taut. an auxiliary cable Adrum coupled with said auxiliary driving mechanism, and an auxiliary cable wound on said cable l drum and adapted to be attached to the oating loa'dtto transmit the motion of the latter to said winch, whereby said load-carrying hook will be caused to move in synchronism with the load to facilitate the attachment and detachment of the latter to and from said hook.

8. Mechanism for lifting floating loads, such as seaplanes, from a rough sea comprising a winch including a main winding drum and a winch motorfa lifting rope; adapted to be, wound on mechanism, shiftable means'adapted to 'render said drum, a load-carrying hook carried by said rope, anauxiliary motor. a differential gear cooperatively connecting both of said motors to said winding drum, the auxiliary motor being dimensipned and designed to exert a continuous pull on said rope sufcient to keep thel same taut, an auxiliary cable drum coupled with said auxiliary motor, and an auxiliary cable wound on said cable drum and 'adapted to be attached to the floating load to transmit the motion of the latter to said main winding drum, whereby said load-carrying hook will be caused to move in synchronism with the load to facilitate the attachment and detachment of the latter toand from said hook. 

